Photographic product and process



July 28, 1964 M. M. MORSE 7 3,142,567

PHOTOGRAPHIC PRODUCT AND PROCESS Filed March 9, 1962 2O Suppor'l'TTTTTTTT Vacuum Deposl'l'ion of Gold Vacuum Deposil'i'on of SilverPholosensllive l TTTTTTTT" Halogen Vapor P h o l'oexpose FIG. 2

T u a r a v :9 {Developed Ep- 7 Negaflve T 'T T T T T T T Evaporal'lonpf Volal'lle Alkali and Volcrl'ile Developer INVENTOR imam- ATTORNEYSUnited States Patent H Delaware Filed Mar. 9, 1962, Ser. No. 182,991

8 Claims. (Cl. 9666) The present invention relates to novel photographicproducts, their production and use, and more particularly, to novelphotosensitive elements, their production and use.

The primary objects of the present invention are the production and useof novel photographic elements comprising photosensitive materialsformed, at least in part, by the vacuum deposition of their componentsupon their support. It has been found that such photosensitive materialspossess characteristics, including virtually grainless structure andsmall mass per unit area, that unexpectedly make feasible a variety ofunusual processing techniques and pictorial results.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the process possessing the severalsteps and the relation and order of one or more of such steps withrespect to each of the others and the product possessing the features,properties and the relation of elements which are exemplified in thefollowing detailed disclosure, and the scope of the application of whichwill be indicated in the claims.

For a fuller understanding of the nature and objects of the presentinvention, reference should be had to the following detailed descriptiontaken in connection with the accompanying drawing wherein:

FIGURE 1 shows successive, exaggerated diagrammatic cross-sectional,views of materials undergoing a process of the present invention; and

FIG. 2 shows successive, exaggerated cross-sectional views of theproduct of the process of FIGURE 1 being used in accordance with thepresent invention.

Generally the processes and products of the present in vention hereindisclosed are based upon the production of a photosensitive stratum byvacuum depositing at least a metal of a photosensitive salt on asupportand then subjecting the metal on the support to halogen vapor.The support, for example, is composed of a suitable plastic such ashydrolyzed cellulose acetate, a suitable paper such as baryta paper or asuitable glass.

The step of vacuum depositing involves either evaporating or sputteringat pressures below one hundred microns of mercury, and usually withinthe range of from 0.1 to 100 microns of mercury, these pressures beingproduced by continuous evacuation to ensure the rapid removal of anygases produced during the vacuum deposition process. The metallicdistribution of the stratum initially formed preferably is in sufiicientconcentration per unit area to give rise to an optical transmission ofatmost 40%. Unusually useful results are achieved when the metaldistribution includes both gold and silver deposited in either sequenceor together. Best results are achieved when the silver is vacuumdeposited in a concentration that by itself would give rise to anoptical transmission of from about 10% to about 30%, the gold isdeposited in a concentration that by itself would give rise to anoptical transmission of from about 10% to about 30% and the gold andsilver are deposited in concentrations which together give rise to anoptical transmission of from about 0.01% to about 1.0%.

Halogenation is effected by subjecting the metallic stratum produced inthe foregoing way to the vapor of elemental halogen, e.g., chlorine,bromine, iodine or combinations thereof or t) volatile halogen salts,e.g., hydroice gen bromide, hydrogen iodide or combinations thereof at asuitable temperature, for example, room temperature. The metallicstratum, preferably, is subjected to the halogen vapor for a periodsufficient to effect substantially complete halogenation, a conditionthat is indicated when the optical transmission of the stratum hasincreased substantially to between about and As noted above,photosensitive strata may be prepared, in accordance with thisinvention, by evaporating silver alone or in combination with gold,followed by halogenation. Where the photosensitive stratum is preparedby evaporating silver as the only metal, the resulting photosensitivesilver halide stratum may be developed by the application of heatalonetoform a negative silver image; this method of development isdisclosed and claimed in the copending application of Edwin H. Land,Serial No. 733,754, filed May 7, 1958 (now abandoned in favor of acontinuation application, Serial No. 176,844, filed February 14, 1962).

Where the photosensitive stratum prepared in accordance with thisinvention includes both silver and gold, it has been found that theexposed photosensitive stratum may be developed to a negative silverimage by the application of vapors of a silver halide developing agent,particularly a silver halide developing agent which exhibits appreciablevolatility at room temperature, e.g., volatile hydroxylamines andhydrazines. Particularly useful results are obtained with a volatilehydroxylamine, such as, N,N-diethyl-hydroxylamine. In conjunction withthe volatile silver halide developing agent, the vapor of a volatilealkali, for example, an amine, such as diethylamine, also may be used.The silver and gold may be deposited in either sequence or together,with the silver being deposited in a concentration that by itself wouldgive rise to an optical transmission of from about 10% to about 30%, andthe gold being deposited in a concentration sufficient per unit area togive rise to an optical transmission of at most 40%. As noted above,best results, including highest sensitivity and speed of development,are achieved when said silver and gold each are deposited in aconcentration which by itself would provide an optical transmission offrom about 10% to about 30%, the coating of gold and silver togetherhaving a total optical transmission of from about 0.01% to about 1.0%,and thereafter halogenating the metallic coating to provide ahalogenated metallic coating having an optical transmission of fromabout 85% to about 100%.

Photosensitivestrata prepared in accordance with this invention andcontaining both gold and silver also may be developed by the applicationof heat alone, asdisclosed and claimed in the abovementioned copendingapplication, Serial No, 733,754.

Example I V 5 FIGURE 1 illustrates the production of a photosensitiveelement in accordance with the present invention.-

As shown, the support is a hydrolyzed cellulose acetate sheet 20,approximately 1 millimeter thick, 3 inches wide and 6 /2 inches long.First, 5 milligrams of gold is evapo-' The photosensitive element ofExample I is photoexposed. Thereafter under a bell jar, this element issub- J jected to the vapor of diethylamine as an alkali andN,N-diethyl-hydroxylamine as a developer. The partial pressures of thediethylamine and the N,N-diethyl-hydroxylamine are the normal partialpressures of those compounds at room temperature. A negative print ofdelicate gradation is produced in approximately five minutes.

Example III Example IV A negative print is obtained in approximately 1minute when the procedure of Example 11 is repeated with aphotosensitive element prepared in the manner described in Example I,except that the optical transmissions of the gold stratum and the goldand silver stratum, respectively, are 39% and 0.80%, and halogenation iseifected by iodine vapors.

Example V A negative print is obtained in approximately 35 seconds whenthe procedure of Example II is repeated with a photosensitive elementprepared in the manner described in Example I, except that the opticaltransmissions of the gold stratum and the gold and silver stratum,respectively, are 29% and 0.10%, and halogenation is effected by iodinevapors. Similar results are obtained when substantially the sameconcentrations of silver and gold are applied but in the reversesequence.

The prints of the above examples may be fixed by reacting the unreducedsilver with a fixing vapor, e.g., hydrogen sulfide, to form a stablesilver salt or by coating with a washing and protecting formulationincluding water and a film-forming polymer.

When the development procedure of, e.g., Example II, was repeatedemploying a photoexposed photosensitive stratum prepared by vacuumdeposition of only silver, very little silver image density wasobserved. This comparison demonstrates the unexpected results obtainedwhere both silver and gold are employed in preparing photosensitivematerials in accordance with this embodiment of the invention.

Photosensitive materials prepared in accordance with this invention maybe developed by aqueous alkaline solutions of a silver halide developingagent, e.g., hydroquinone, which may be applied by spraying or lightlyswabbing the developer solution onto the exposed photosensitivematerial; and they also may be employed in diffusion transfer processes,wherein a water-soluble silver complex is formed by a silver halidesolvent with unexposed and undeveloped silver halide, and saidwater-soluble silver complex is transferred by diffusion to a superposedsilverreceptive stratum to provide a silver transfer image.

This application is a continuation-in-part of my copending application,Serial No. 733,753, filed May 7, 1958 (now abandoned).

Since certain changes may be made in the above product and processwithout departing from the scope of the invention herein involved, it isintended that all matter contained in the above description and shown inthe accompanying drawing shall be interpreted as illustrative and not ina limiting sense.

What is claimed is:

1. A process of forming a photosensitive element, said processcomprising the steps of vacuum depositing gold and silver on a supportto form a metallic coating, said silver being deposited in aconcentration which, by itself, would provide an optical transmission offrom about 10% to about 30%, said gold being deposited in aconcentration which, by itself, would be a metallic coating having anoptical transmission of from about 10% to at most 40%, said coating ofgold and silver together having a total optical transmission of fromabout 0.01% to about 1.0%, and halogenating said metallic coating bycontacting said metallic coating with halogen vapors provided by amember of the group consisting of elemental chlorine, elemental bromine,elemental iodine, and volatile salts of said elemental halogens for atime sufficient to provide a halogenated metallic coating having anoptical transmission of from about to about 2. A photosensitive elementprepared by the process of claim 1.

3. The process of developing a photoexposed photosensitive stratumformed by the process of claim 1, said development being effected bycontacting said exposed photosensitive stratum with the vapor of avolatile organic silver halide developing agent.

4. The process of claim 3, wherein said development is effected at roomtemperature.

5. The process of claim 3, wherein said volatile organic silver halidedeveloping agent is selected from the class consisting of hydroxylaminesand hydrazines.

6. The process of claim 3, including the step of treating the developedphotosensitive stratum with hydrogen sulfide vapors.

7. The process which comprises photoexposing a photosensitive elementformed by the process of claim 1, and developing said photoexposedphotosensitive element by contacting it, at room temperature, withvapors of diethylamine and N,N-diethyl-hydroxylamine.

8. The process as defined in claim 1, wherein said gold is depositedprior to said silver, said gold layer having an optical transmission ofabout 30%, and said halogen vapors are iodine vapors.

References Cited in the file of this patent UNITED STATES PATENTS2,153,628 Knoll Apr. 11, 1939 2,239,452 William et al. Apr. 22, 19412,399,083 Waller Apr. 22, 1946 2,439,983 Morgan et al. Apr. 20, 19482,706,157 Sainsbury et al Apr. 12, 1955 OTHER REFERENCES Yamada et al.:Chemical Abstracts, vol. 50, pages 11147-8.

Glafkides: Photograph Chemistry, 1., Fountain Press, London (1958), page319.

1. A PROCESS OF FORMING A PHOTOSENSITIVE ELEMENT, SAID PROCESSCOMPRISING THE STEPS OF VACUUM DEPOSITING GOLD AND SILVER ON A SUPPORTTO FORM A METALLIC COATING, SAID SILVER BEING DEPOSITED IN ACONCENTRATION WHICH, BY ITSELF, WOULD PROVIDE AN OPTICAL TRANSMISSION OFFROM ABOUT 10% TO ABOUT 30%, SAID GOLD BEING DEPOSITED IN ACONCENTRATION WHICH, BY ITSELF, WOULD BE A METALLIC COATING HAVING ANOPTICAL TRANSMISSION OF FROM ABOUT 10% TO AT MOST 40%, SAID COATING OFGOLD AND SILVER TOGETHER HAVING A TOTAL OPTICAL TRANSMISSION OF FROMABOUT 0.01% TO ABOUT 1.0%, AND HALOGENATING SAID METALLIC COATING BYCONTACTING SAID METALLIC COATING WITH HALOGEN VAPORS PROVIDED BY AMEMBER OF THE GROUP CONSISTING OF ELEMENTAL CHLORINE, ELEMENTAL BROMINE,ELEMENTAL IODINE, AND VOLATILE SALTS OF SAID ELEMENTAL HALOGENS FOR ATIME SUFFICIENT TO PROVIDE A HALOGENATED METALLIC COATING HAVING ANOPTICAL TRANSMISSION OF FROM ABOUT 85% TO ABOUT 100%.
 3. THE PROCESS OFDEVELOPING A PHOTOEXPOSED PHOTOSENSITIVE STRATUM FORMED BY THE PROCESSOF CLAIM 1, SAID DEVELOPMENT BEING EFFECTED BY CONTACTING SAID EXPOSEDPHOTOSENSITIVE STRATUM WITH THE VAPOR OF A VOLATILE ORGANIC SILVERHALIDE DEVELOPING AGENT.